In a move that will give SportsNet NY instant on-air credibility, it will announce today that Gary Cohen is moving over from radio to be the new voice of the Mets on TV, The Post has learned.

Reached by phone yesterday, Cohen declined to comment, but SNY has a teleconference set up for 11:30 a.m. today to make the news official.

After Dave O’Brien chose ESPN over SNY two weeks ago, SNY and Met executives honed in on Cohen to be their man in the TV booth. Cohen is expected to work nearly all of the Mets’ games on TV.

The Mets’ owner, Fred Wilpon, has been outspoken in wanting his TV voice to call all the team’s games. This hurt the chances of Ted Robinson because he works grand slam tennis for NBC and USA.

Cohen is likely making the move in large part because television is more lucrative financially than radio. As a radio play-by-player, besides being on top of the action, Cohen was known to be critical when it was called for. Under greater scrutiny on TV, it will say a lot about SNY and Mets’ ownership if Cohen is not pressured to tone down his assessments.

The only foreseeable drawback for Cohen is if he will be able to demonstrate the levity that TV sometimes demands compared to the nuts-and-bolts of radio broadcasting.

Cohen’s partners on TV have yet to be decided. SNY executives have spoken to Keith Hernandez and David Cone. Al Leiter is another possibility.

On the radio side, WFAN – which is on the verge of signing a new deal with the Mets – could make Howie Rose the lead play-by-player and then search for a new No. 2 man.

Cohen, who had been in Shea’s radio booth for 17 years, grew up in Queens as a Mets fan. Cohen also calls Seton Hall basketball on ESPN Radio.